An acidic etching additive used in the production of precise fine circuits using laser blind micro-via technology

Abstract

An acidic etching additive for use in the production of precise fine circuits using laser micro-blind buried via technology, characterized in that the acidic etching additive comprises the following components: 0.05-5 parts of a modified benzotriazole, 0.05-5 parts of a water-soluble tetrazole heterocyclic compound, 10-30 parts of triethanolamine phosphate, 5-20 parts of a small molecule alcohol cosolvent, 1-25 parts of a wetting and penetrating agent, 0.1-10 parts of a low-foaming surfactant, and water; wherein the modified benzotriazole is obtained by reacting benzotriazole with 3-bromo-2-hydroxypropyltrimethylammonium bromide and 16-bromo-hexadecyltrimethylammonium bromide. The acidic etching additive for use in the production of precise fine circuits using laser micro-blind buried via technology provided by the present invention can effectively improve the etching factor of circuit production, reduce lateral etching of precise fine circuits, reduce circuit burrs, and improve etching uniformity.

Description

Technical Field

[0001] The invention belongs to the technical field of surface treatment, and in particular relates to an acid etching additive used in the production of precise fine circuits using a laser blind micro-hole buried hole technology. Background Art

[0002] With the widespread adoption of AI technology, electronic products in various industries, such as mobile communications, military, medical, aerospace, and automotive, are moving towards greater precision and miniaturization. This trend has driven a year-on-year increase in the market share of high-end PCBs, such as HDI boards and SLP-type substrates, in the PCB industry.

[0003] High-density interconnect (HDI) boards are high-end circuit boards with a relatively high density of circuits, manufactured using laser micro-blind buried via technology. They utilize multiple lamination processes, laser drilling, electroplating and filling, and vacuum etching to achieve electrical connections between each layer of circuitry. These multi-layer, high-precision printed circuit boards are characterized by their thinness, compactness, high precision, high density, and high integration. The drilling process for HDI boards differs from traditional PCBs in that, rather than using a mechanical drill, laser drilling is employed instead. The hole diameter is typically 3-5 mils (0.076-0.127mm), and the track width is typically 3-4 mils (0.076-0.10mm). This significantly reduces the size of the pads, enabling the arrangement of denser BGAs and QFPs within the HDI board, and more precise circuits per unit area.

[0004] Compared to HDI boards, substrate-like PCBs (SLPs) feature more stacked layers, smaller line widths and line spacings, and can accommodate more functional modules. Their specifications and manufacturing processes are closer to IC package substrates, making them the future mainstream printed circuit board (PCB) in the PCB market. They can reduce line widths and line spacing from HDI boards' 40 / 50μm to 20 / 35μm, meaning the minimum line width and line spacing decreases from HDI's 50μm to less than 30μm in SLPs. This allows them to accommodate twice as many electronic components within the same footprint as HDI. In the etching process for fine circuitry in PCB fabrication, hydrochloric acid / hydrogen peroxide or hydrochloric acid / sodium chlorate systems are most commonly used. These etchants offer minimal side erosion, easily controllable etching rates, and the ability to regenerate copper. They are widely used in the industry.

[0005] For precision fine-line etching with line widths and spacings ≤40 / 50μm on HDI boards and SLP-like substrates, precise line widths and smooth edges are essential, placing high demands on the etching process. The etching quality can directly impact the quality of the PCB manufacturing process, affecting the accuracy and quality of the high-density fine-line pattern and even the reliability of signal transmission.

[0006] Conventional acidic etchants are sufficient for etching ordinary double-sided / multi-layer PCBs with line widths / line spacings ≥75 / 75μm, with an etching factor ≥3.0 and minimal burr side etching. However, when etching the precise line widths / line spacings of HDI boards and SLP-like substrates, these etchants are less effective. In actual operations, these etchants often exhibit quality issues such as insufficient etching uniformity, excessive line side etching, significant etching edge effects, and poor etching factors.

[0007] In summary, there is an urgent need to develop a new etching additive to solve the problems existing in the prior art. Summary of the Invention

[0008] Based on this, the present invention provides an acidic etching additive for use in the production of precise fine circuits using laser micro-blind buried hole technology, which can effectively improve the etching factor of circuit production, reduce lateral corrosion of precise fine circuits, reduce circuit burrs, and improve etching uniformity.

[0009] The present invention discloses an acidic etching additive for use in the production of precise fine circuits using a laser blind micro-via buried hole technology. The acidic etching additive comprises the following components:

[0010]

[0011] The modified benzotriazole is obtained by reacting benzotriazole with 3-bromo-2-hydroxypropyltrimethylammonium bromide and 16-bromo-hexadecyltrimethylammonium bromide.

[0012] Furthermore, the modified benzotriazole is preferably present in an amount of 0.05-5 parts.

[0013] Furthermore, the water-soluble tetrazole heterocyclic compound is selected from one or more of 5-aminotetrazole, 2-(2-methoxy-4-nitrobenzene)-3-(4-nitrobenzene)-5-(2,4-disulfonylbenzene)-2H-tetrazole monosodium salt, and 5-methyl-1H-tetrazole.

[0014] Furthermore, the water-soluble tetrazole heterocyclic compound is preferably 0.05-5 parts.

[0015] Furthermore, the amount of triethanolamine phosphate is preferably 10-30 parts.

[0016] Furthermore, the small molecule alcohol cosolvent is selected from one or two of methanol, ethanol, and isopropanol, preferably 5-20 parts.

[0017] Furthermore, the wetting and penetrating agent is a diol ether structure substance having hydroxyl groups, preferably 1-25 parts.

[0018] Furthermore, the glycol ether structural substance having hydroxyl groups is selected from one or more of dipropylene glycol methyl ether, triethylene glycol butyl ether, propylene glycol butyl ether, and polyethylene glycol methyl ether.

[0019] Furthermore, the low-foaming surfactant is selected from one or more of alkyl polyglycoside APG-Z6, 2-methyl-2,4-pentanediol polyoxypropylene polyoxyethylene ether, polyethylene glycol PEG-200, and polyether Pluronic F-68.

[0020] Furthermore, the low-foaming surfactant is preferably 0.1-10 parts.

[0021] Furthermore, the preparation method of the acidic etching additive used in the production of precise fine circuits using the laser blind micro-via buried technology comprises the following steps:

[0022] S1, using benzotriazole, 3-bromo-2-hydroxypropyltrimethylammonium bromide, 16-bromo-hexadecyltrimethylammonium bromide, and NaOH as raw materials and ethanol as solvent, conducting a constant temperature reflux reaction to obtain a modified benzotriazole;

[0023] S2. blending the modified benzotriazole and a water-soluble tetrazole heterocyclic compound in a mass ratio of 1-5:1 to obtain a mixture;

[0024] S3. Add water, small molecule alcohol cosolvent, wetting and penetrating agent, the mixture, triethanolamine phosphate, and low-foaming surfactant into the container in sequence, and stir at a constant temperature to obtain the acid etching additive used for the production of precise fine circuits using laser micro-blind buried hole technology.

[0025] Furthermore, in step S3, 1 / 4 of deionized water is first added, and then a small molecule alcohol cosolvent, a wetting and penetrating agent, the mixture, triethanolamine phosphate, and a low-foaming surfactant are added. After stirring evenly, the remaining deionized water is added to the scale level, and the mixture is stirred in a cycle at a constant temperature of 40°C for 30 minutes to obtain the acidic etching additive used in the production of precise fine circuits using laser micro-blind buried hole technology.

[0026] Furthermore, the molar ratio of the benzotriazole, 3-bromo-2-hydroxypropyltrimethylammonium bromide, 16-bromo-hexadecyltrimethylammonium bromide, and NaOH is 1:1-3:1-3:6.

[0027] Furthermore, the constant temperature reflux reaction temperature is 70-90° C., and the reaction time is 5-8 h.

[0028] The base liquid used for etching copper plates in the printed circuit board industry is called acid etching mother liquid. Compared with the base liquid, the replenishing liquid that does not contain copper is called acid etching sub-liquid.

[0029] The acidic etching additive of the present invention is applied to the acidic etching mother solution in an addition ratio range of 0.5-5%. It should be noted that copper chloride is used as the copper ion in the acidic etching mother solution, and the copper ion concentration is controlled within 120-160 g / L. Within this concentration range, a stable etching rate can be maintained. If the concentration is too low, the etching rate will be too low, resulting in etching residual copper. If the concentration is too high, crystallization is likely to occur, affecting the etching reaction.

[0030] The concentration of hydrochloric acid, the source of acidity, is controlled within the range of 1.2-2.5 mol. This concentration maintains the etching process, prevents oxidation of the copper surface, and prevents copper ions from crystallizing and clogging the pipes and etching nozzles due to high concentration, resulting in poor etching patterns.

[0031] The temperature of the etching reaction is selected to be 45-55°C. If the temperature is too low, the etching reaction will be too slow. If the temperature is too high, the acid mist will evaporate greatly, the reaction will be violent, and the etching speed will be difficult to control.

[0032] The etching method is horizontal spray mode, and the etching nozzle pressure is controlled at 1.2-3.0kg / cm 2 , avoiding the problems of copper chloride crystals clogging pipes and etching line nozzles due to excessive copper ions in the etching solution; within this spray pressure range, it can effectively prevent side corrosion caused by damaged anti-corrosion protective film, and at the same time prevent copper residue problems on the front side of the copper line due to the anti-corrosion protective film not being removed in time.

[0033] The present invention has the following beneficial effects:

[0034] The acidic etching additive provided by the present invention is used for the production of precise fine circuits using laser blind micro-via buried technology. The modified benzotriazole is obtained by reacting benzotriazole with 3-bromo-2-hydroxypropyltrimethylammonium bromide and 16-bromo-hexadecyltrimethylammonium bromide. On the one hand, the nitrogen atoms of the modified benzotriazole can provide electrons to connect with copper through coordination bonds, alternately forming chain polymers to form a protective film on the copper surface; on the other hand, the quaternary ammonium cationic structure can be adsorbed by the metal surface and arranged on the metal surface to carry a positive charge, thereby preventing hydrogen ions from approaching the metal surface, thereby achieving a corrosion inhibition effect. The two effects complement each other, so that the modified benzotriazole has a good corrosion inhibition effect. In addition, the introduction of hydroxypropyl groups strengthens its electron-donating ability, and the introduction of long-chain structures gives it better film-forming properties, further enhancing its corrosion inhibition effect.

[0035] At the same time, water-soluble tetrazole heterocyclic substances have good compatibility with modified benzotriazole. They can combine with cuprous ions to form ligand polymers, enhancing the density of the anti-corrosion film. When combined with modified benzotriazole, they further enhance the product's corrosion inhibition and effectively prevent lateral corrosion. Low-foaming surfactants have excellent wetting and penetration properties and reduce surface tension, allowing modified benzotriazole to be more evenly adsorbed and dispersed on the copper surface, forming an anti-corrosion film and enhancing the corrosion inhibition effect.

[0036] The modified benzotriazole of the present invention achieves a good corrosion protection effect without affecting the etching rate by synergizing with other substances in the formula, effectively improving the etching factor of circuit production, thereby facilitating the reduction of lateral etching of precision fine circuits, reducing circuit burrs, and improving etching uniformity, thereby overcoming the shortcomings of the existing technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is an etching effect diagram of the acidic etching additive prepared in Example 1 for the production of precise fine circuits using laser blind micro-via buried technology;

[0038] in,

[0039] Figure 1 (a) is the etching effect image with line width / line spacing L / S = 40μm / 40μm and copper thickness of 25μm;

[0040] Figure 1 (b) is the etching effect image with line width / line spacing L / S = 50μm / 50μm and copper thickness of 30μm;

[0041] Figure 1 (c) is the etching effect image with line width / line spacing L / S = 50μm / 30μm and copper thickness of 26μm;

[0042] Figure 1 (d) is the etching effect image with line width / line spacing L / S = 40μm / 40μm and copper thickness of 25μm;

[0043] Figure 1 (e) is the etching effect image with line width / line spacing L / S = 35μm / 35μm and copper thickness of 18μm;

[0044] Figure 1 (f) is the etching effect diagram when the line width / line spacing L / S = 30μm / 30μm and the copper thickness is 18μm.

[0045] Figure 2 The etching effect diagram of the acidic etching additive prepared in the examples and comparative examples;

[0046] in,

[0047] Figure 2 (a) is the etching effect diagram of Example 1 for L / S = 50 μm / 30 μm and copper thickness of 26 μm;

[0048] Figure 2 (b) is the etching effect diagram of Example 2 for L / S = 50 μm / 30 μm and copper thickness of 26 μm;

[0049] Figure 2 (c) is the etching effect diagram of comparative example 1 with L / S=40μm / 40μm and copper thickness of 25μm. DETAILED DESCRIPTION

[0050] In order to more clearly illustrate the technical solutions of the present invention, the following examples are given. Unless otherwise stated, the raw materials, reactions and post-processing methods mentioned in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0051] The 16-bromo-hexadecyltrimethylammonium bromide in the embodiment of the present invention is homemade, and its preparation method comprises the following steps:

[0052] 1,16-dibromohexadecane (195.6 g, 0.509 mol) was added to 500 mL of acetone solvent, and trimethylamine (34.5 g, 0.151 mol) was quickly added at 0 ° C. The mixture was sealed and stirred at room temperature for 24 hours, and then the solvent was removed by rotary evaporation to obtain a yellow viscous liquid. The yellow viscous liquid was dissolved by heating with a mixed solvent of acetone and ethanol in a volume ratio of 3:1. After cooling to room temperature and standing, the precipitated solid was removed by filtration, and the solvent was removed under reduced pressure. Acetone was added to the residue and heated to dissolve it. The mixture was allowed to stand again. Solids precipitated and were filtered off under reduced pressure to obtain a solid product. The powder was dried in vacuo at 60 ° C to obtain 16-bromo-hexadecyltrimethylammonium bromide.

[0053] Examples 1-15

[0054] The substances and concentrations used in Examples 1-15 are shown in Table 1

[0055] Table 1: Substances and concentrations used in Examples 1-15

[0056]

[0057]

[0058]

[0059]

[0060]

[0061] The preparation method of Example 1-15 comprises the following steps:

[0062] S1. Using ethanol as a solvent, benzotriazole, 3-bromo-2-hydroxypropyltrimethylammonium bromide, 16-bromo-hexadecyltrimethylammonium bromide, and NaOH in a molar ratio of 1:2:2:6 were mixed and refluxed at 79° C. for 6 h to obtain a modified benzotriazole.

[0063] S2. Blending the modified benzotriazole and the water-soluble tetrazole heterocyclic compound according to the above-mentioned parts by mass to obtain a mixture;

[0064] S3. According to the above-mentioned mass fractions, first add 1 / 4 of deionized water into the reactor, then add a small molecule alcohol cosolvent, a wetting and penetrating agent, the mixture, triethanolamine phosphate and a low-foaming surfactant, stir evenly, add the remaining deionized water, circulate and stir at a constant temperature of 40°C for 30 minutes, and obtain the acidic etching additive used for the production of precise fine circuits using laser micro-blind buried hole technology.

[0065] Comparative Examples 1-6

[0066] The substances and concentrations used in Comparative Examples 1-6 are shown in Table 2

[0067] Table 2: Substances and concentrations used in Examples 1-15

[0068]

[0069]

[0070]

[0071] The preparation method of Comparative Examples 1-6 comprises the following steps:

[0072] The components were added into a reaction kettle according to the above mass fractions, mixed, and circulated and stirred at a constant temperature of 40° C. for 30 min to obtain an acidic etching additive.

[0073] The difference between Comparative Examples 7-9 and Example 1 is that modified benzotriazole A, modified benzotriazole B or modified benzotriazole C are used in equal parts by mass to replace modified benzotriazole, and the other ingredients and preparation methods are the same as those in Example 1;

[0074] The modified benzotriazole A is prepared by replacing 16-bromo-hexadecyltrimethylammonium bromide with 2-bromoethyltrimethylammonium bromide in step S1, with other conditions being the same;

[0075] The modified benzotriazole B is prepared by replacing 16-bromo-hexadecyltrimethylammonium bromide with 3-bromo-2-hydroxypropyltrimethylammonium bromide in step S1 (i.e., deleting 16-bromo-hexadecyltrimethylammonium bromide), with other conditions being the same;

[0076] The modified benzotriazole C is as follows: in step S1, 16-bromo-hexadecyltrimethylammonium bromide is used to replace 3-bromo-2-hydroxypropyltrimethylammonium bromide (ie, 3-bromo-2-hydroxypropyltrimethylammonium bromide is deleted), and other conditions are the same.

[0077] Test Case

[0078] The etching effects of the acidic etching additives obtained in the examples and comparative examples for the production of fine circuits using laser blind micro-via buried technology were tested. The specific etching conditions were:

[0079] The parameters of the plate to be etched with fine lines covered by the anti-corrosion photoresist film dry film are as follows:

[0080] Line width / line spacing L / S = 50μm / 50μm, copper thickness 30μm;

[0081] Line width / line spacing L / S = 50μm / 30μm, copper thickness 26μm;

[0082] Line width / line spacing L / S = 40μm / 40μm, copper thickness 25μm;

[0083] Line width / line spacing L / S = 35μm / 35μm, copper thickness 18μm;

[0084] Line width / line spacing L / S = 30μm / 30μm, copper thickness 18μm.

[0085] Etching was performed using a vacuum two-fluid etcher with the etching temperature set at 50°C, the copper ion concentration set at 130 g / l, the hydrochloric acid concentration set at 1.8 mol, the etching solution density set at 1.292, and the upper spray pressure set at 2.6 kg / cm 2 , the lower spray pressure is set to 2.3kg / cm 2 The etching time is set appropriately for boards of different specifications according to different copper thickness parameters. Etching additives are added according to different examples and comparative examples, and the concentration of the etching solution is kept the same as that of the test group.

[0086] A portion of each substrate etched by different test groups was cut off, embedded in cold embedding resin, and polished to enable observation of the cross-section of the wiring. The maximum thickness of the copper circuit film on the side was measured using a scanning electron microscope (SEM) image.

[0087] Scanning electron microscope (SEM) images were used to measure the top width, bottom width, and copper thickness of the etched copper wiring. The etching factor calculation formula was used to calculate and evaluate the effect of the circuit's side corrosion protection:

[0088] Etching factor = 2A / (BT);

[0089] Where A is the thickness of copper; T is the width of the top in μm; and B is the width of the bottom in μm.

[0090] The results are shown in Table 3 and Figure 1 、 Figure 2 shown.

[0091] Table 3 Etching factors of various embodiments and comparative examples

[0092]

[0093] Figure 1 This is an etching effect diagram of the acidic etching additive prepared in Example 1 for the production of precise fine circuits using laser blind micro-via buried technology;

[0094] in,

[0095] Figure 1 (a) is the etching effect image with line width / line spacing L / S = 40μm / 40μm and copper thickness of 25μm;

[0096] Figure 1 (b) is the etching effect image with line width / line spacing L / S = 50μm / 50μm and copper thickness of 30μm;

[0097] Figure 1 (c) is the etching effect image with line width / line spacing L / S = 50μm / 30μm and copper thickness of 26μm;

[0098] Figure 1 (d) is the etching effect image with line width / line spacing L / S = 40μm / 40μm and copper thickness of 25μm;

[0099] Figure 1 (e) is the etching effect image with line width / line spacing L / S = 35μm / 35μm and copper thickness of 18μm;

[0100] Figure 1 (f) is the etching effect diagram when the line width / line spacing L / S = 30μm / 30μm and the copper thickness is 18μm.

[0101] Figure 2 The etching effect diagram of the acidic etching additive prepared in the examples and comparative examples;

[0102] in,

[0103] Figure 2 (a) is the etching effect diagram of Example 1 for L / S = 50 μm / 30 μm and copper thickness of 26 μm;

[0104] Figure 2 (b) is the etching effect diagram of Example 2 for L / S = 50 μm / 30 μm and copper thickness of 26 μm;

[0105] Figure 2 (c) is the etching effect diagram of comparative example 1 with L / S=40μm / 40μm and copper thickness of 25μm.

[0106] according to Figure 1 、 Figure 2 It can be seen that the acidic etching additive prepared in the embodiment for the production of precise fine circuits using the laser blind micro-via buried technology has a good etching effect, which is expressed in terms of etching factor. The etching factor is 5-8, and the performance is better than that of the comparative example.

[0107] As can be seen from Table 3, when etching five different etching plates, the etching factors of Examples 1-15 were significantly higher than those of Comparative Examples 1-6, indicating that the acidic etching additive prepared by the present invention for the production of precise fine circuits using laser blind micro-via technology has excellent anti-side etching effects. In addition, the technical effects of Comparative Examples 7-9, which replaced or deleted 3-bromo-2-hydroxypropyltrimethylammonium bromide and 16-bromo-hexadecyltrimethylammonium bromide, all showed a decrease, demonstrating that the simultaneous introduction of long-chain structures and hydroxypropyl functional groups has a certain synergistic effect, significantly promoting the improvement of technical effects. To achieve strong corrosion inhibition performance, both are indispensable. From these results, it can be seen that the present invention can form copper wiring with few undercuts and pits and excellent straightness.

[0108] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations that come within the meaning and range of equivalents of the claims be embraced therein.

[0109] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. An acidic etching additive used in the production of precise fine circuits using laser blind micro-via buried technology, characterized in that: The acidic etching additive comprises the following components in parts by mass: 0.05-5 parts of modified benzotriazole 0.05-5 parts of water-soluble tetrazole heterocyclic compound 10-30 parts of triethanolamine phosphate 5-20 parts of small molecule alcohol cosolvent 1-25 parts of wetting and penetrating agent 0.1-10 parts of low-foaming surfactant 5-85 parts water; Wherein, the modified benzotriazole is obtained by reacting benzotriazole with 3-bromo-2-hydroxypropyltrimethylammonium bromide and 16-bromo-hexadecyltrimethylammonium bromide; The preparation method of the modified benzotriazole is: Benzotriazole, 3-bromo-2-hydroxypropyltrimethylammonium bromide, 16-bromo-hexadecyltrimethylammonium bromide and NaOH are used as raw materials and ethanol is used as solvent to carry out a constant temperature reflux reaction to obtain a modified benzotriazole; The molar ratio of the benzotriazole, 3-bromo-2-hydroxypropyltrimethylammonium bromide, 16-bromo-hexadecyltrimethylammonium bromide, and NaOH is 1:1-3:1-3:6; The constant temperature reflux reaction temperature is 70-90 ° C, and the reaction time is 5-8 h; The water-soluble tetrazole heterocyclic compound is selected from one or more of 5-aminotetrazole, 2-(2-methoxy-4-nitrobenzene)-3-(4-nitrobenzene)-5-(2,4-disulfonylbenzene)-2H-tetrazole monosodium salt, and 5-methyl-1H-tetrazole.

2. The acidic etching additive used in the production of precise fine circuits using laser blind micro-via buried hole technology according to claim 1, characterized in that: The small molecule alcohol cosolvent is selected from one or two of methanol, ethanol and isopropanol.

3. The acidic etching additive used in the production of precise fine circuits using laser blind micro-via buried technology according to claim 1, characterized in that: The wetting and penetrating agent is a diol ether structure material having hydroxyl groups.

4. The acidic etching additive used in the production of precise fine circuits using laser blind micro-via buried hole technology according to claim 3, characterized in that: The glycol ether structural material having hydroxyl groups is selected from one or more of dipropylene glycol methyl ether, triethylene glycol butyl ether, propylene glycol butyl ether, and polyethylene glycol methyl ether.

5. The acidic etching additive used for the production of precise fine circuits using laser blind micro-via buried technology according to claim 1, characterized in that: The low-foaming surfactant is selected from one or more of alkyl polyglycoside APG-Z6, 2-methyl-2,4-pentanediol polyoxypropylene polyoxyethylene ether, polyethylene glycol PEG-200, and polyether Pluronic F-68.

6. The method for preparing the acidic etching additive for use in the production of precise fine circuits using laser blind micro-via buried hole technology according to any one of claims 1 to 5, characterized in that: The steps include: The modified benzotriazole and the water-soluble tetrazole heterocyclic compound are blended in a mass ratio of 1-5:1 to obtain a mixture; Water, small molecule alcohol cosolvent, wetting penetrant, the mixture, triethanolamine phosphate, and low-foaming surfactant are sequentially added into a container and stirred at a constant temperature to obtain the acid etching additive used for the production of precise fine circuits using laser micro-blind buried hole technology.

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